Fan for grain-separators



(No Model.)

J. HAWK.

FAN FOR GRAIN SEPARATORSQ No. 336,567. Patented Feb. 23, 1886.

' WITNESSES M M I/VVEIVTOR NTTED STATES PATENT OFFICE,

JACOB HAWK, OF CANTON, OHIO.

FAN FOR GRAIN-SEPARATORS.

fiPEGIPICATION forming part of Letters Patent No. 336,567, datedFebruary 23, 1886.

Application filed Sept-ember 10, 1885. Serial No. 176,718. (No model.)

To all whom it may concern:

Be it known that I, JACOB HAWK, a citizen of the United States, and aresident of Canton, county of Stark, State of Ohio, have invented a newand useful Improvement in Fans for Grain-Separators, of which thefollowing is a full, clear, and exact description, reference being hadto the accompanying drawings, making part of this specification.

My invention relates to an improvement in grain-separators; and itconsists in the combin'ation,with vibrating riddles, of a fan having alarger diameter at its middle section than at its ends.

In the accompanying drawings, Figure 1 is a side elevation ofthrashing-machine with the side board removed, showing the working partswith my improvements attached. Fig. 2 is a View in perspective of thefan, and Fig. 3 is a detached View in perspective of one of thefan-blades.

a b c d efg represent the frame-work of the body of the machine. Aisthevibrator, which may be constructed after any of the well-known plans, orit may consist of a series of notched boards arranged parallel to eachother, and of such distance apart as may be best adapted to carry thestraw out of the machine, the grain falling through the vibrating tableto a return-board, thence to the riddles in the usual Way.

The winnowing apparatus is constructed as follows: A, Fig. 1, representsthe fan or winnowing wheel, B the vibrating riddle-snpporting shoe, C Gthe wire screens or riddles, and D D spouts by which the thrashed grainis conducted to the riddles.

The shoe B may be supported and vibrated by any of the well-known andapproved plans, and the riddles such as are usually provided for suchmachines, as my invention relates particularly to the construction ofthe fan and its relation to the shoe and riddles.

Vith the winnowing-fans having the same diameter throughout their entirelcngth,it has been difficult, if not impossible, to" obtain a properdistribution of wind-blast over all arts of the riddles, being alwaysweaker in the middle of the riddle, in proportion to therequirements,than at the sides,and if the speed of the fan be increasedso as to properly chaff and clean the grain on the middle section. of

the riddle, the blast will be so strong at the sides that it will carryout large quantities of grain. There may be two reasons for this first,because there is more grain deposited on the middle section than on theend section of the riddle; second, because of the increased width of themodern separators.

To obtain a more perfect separation of the grain from the straw andchaff, the separating and winnowing parts of thrashing and separatingmachines have been made wider than the length of the thrashing-cylinder,to wit: A twenty-four-inch cylinder would have a thirty-four'inchseparator, athirty-inch cylinder a forty-two-inch separator, athirtythreeinch cylinder a forty-liveinch separator, and athirty-siX-inch cylinder a forty-eight-inch separator. The length of thefan is always the full width of the inside of the separator;consequently the length is out of proportion to the diameter, and theresult is the blast is liable to be the weakest from the center of thefan, where it should be the strongest.

The demand, in fact the necessity, for wide separators in which thestraw may be so spread out as to secure a more perfect separation of thegrain from the straw must be followed up with an increased length offan, and the difficulties arising from this increased width of separatorcould not be overcome by increasing the diameter of the fan throughoutits entire length.

All fans constructed in the ordinary manner, over two feet in length,placed inside the walls of a separator, throw off a greater blast at theends than at its center. This is occasioned by the fact that the supplyof air cannot reach the center of the fan when the latter is driven at aproper rate of speed.

In all thrashingmachines there is more grain thrashed in the middle ofthe machine than at the sides, and as a result more grain and chaff aredeposited at or near the middle of the riddle. It follows that theadditional amount of matter deposited at or near the center of theriddle requires a proportional increase of blast to thoroughly separatethem; and to accomplish a thorough separation I provide a fan wheelwhich has alarger diameter through its middle section, from E to E, thanthrough the end section, and should be in proportion to the width of theseparator; but with an increased diam- ICO eter 0f the middle section ofthe fan the increased distance traveled by said enlarged section willcause an increased flow of air to the center of the middle sectiomand asa result an increased blast from the middle section.

To obtain a properly-proportioned Windblast over the riddle for athirty-four-inch separator, the diameter of the middle section of thefan for about one-third its length should be two inches larger indiameter than at the ends, and fora forty-eight-i1ich separator themiddle section should be about four inches larger in diameter than theends, and they may be graded to suit the intermediate sizes. The averagediameter of fan is twenty-four inches, average length of bladetl1irty-nine inches,and average breadth of central portion ofthe bladeabout seven inches.

In the construction of the fan I prefer to cut away the ends of theblades A", as shown in Figs. 2 and 3, reducing the end sections to asmaller diameter than the middle section. The middle section, beinglarger in diameter, will travel farther and faster than the endsections, and the result is the ejection of astronger blast of wind fromthe middle than the end sections.

Having fully described my invcntion,what I claim as new, and desire tosecure by Letters Patent, is

In a grain thrashing and separating machine,the combination,withvibrating riddles, of a fan having a larger diameter atits middlesection than at its ends, substantially as and for the purpose setforth.

In testimony whereof I have hereunto set 5 my hand this 8th day ofSeptember,A.D. 1885.

JACOB HAWK. Witnesses:

CHAS. R. MILLER, W. K. MILLER.

